Compositional measurement of gas emissions in the Eastern Carpathians (Romania) using the Multi-GAS instrument: Approach for in situ data gathering at non-volcanic areas

Abstract

The Multi-GAS, a robust and low-cost instrument for real-time in-situ gas measurements, has previously been used mainly for compositional measurements of active volcanic plumes. Here we demonstrate novel use of a specially designed Multi-GAS instrument adapted to low temperature degassing areas. We performed compositional measurements in the Eastern Carpathians on dry and bubbling gas emissions using a sensor kit that allows measurement of CO2, CH4 and H2S (three major components of low-temperature hydrothermal/volcanic manifestations). Our results demonstrate good agreement between Multi-GAS measurements and independently obtained CO2 concentrations from gas chromatography. We also provide some novel H2S information for some anomalous sites, which we relate to possible alteration processes of sulphide minerals. The use of Multi-GAS in such environments could open new possibilities for data collection at non-volcanic areas and exploration of mineral resources. Moreover, it can also be a useful tool in exploration surveys to select the best sampling sites for more detailed laboratory measurements.